Publications by authors named "Emily C Crossley"
Article Synopsis
- Human monocytotropic ehrlichiosis (HME) is a serious tick-borne disease caused by the bacterium Ehrlichia chaffeensis, which can be modeled in mice using Ehrlichia muris and Ixodes ovatus Ehrlichia (IOE).
- Researchers found that persistent E. muris infection helps mice develop immune memory that protects against subsequent IOE infections, while a sublethal dose of IOE does not offer the same protection.
- The study showed that untreated mice with persistent E. muris infections had more memory T cells and regulatory T cells, indicating that ongoing infections enhance the immune response, while those treated with doxycycline were more susceptible to later infections with IOE.
Infection with gram-negative monocytotropic Ehrlichia strains results in a fatal toxic shock-like syndrome characterized by a decreased number of Ehrlichia-specific CD4(+) Th1 cells, the expansion of tumor necrosis factor alpha (TNF-alpha)-producing CD8(+) T cells, and the systemic overproduction of interleukin-10 (IL-10) and TNF-alpha. Here, we investigated the role of CD4(+) and CD8(+) T cells in immunity to Ehrlichia and the pathogenesis of fatal ehrlichiosis caused by infection with low- and high-dose (10(3) and 10(5) bacterial genomes/mouse, respectively) ehrlichial inocula. The CD4(+) T-cell-deficient mice showed exacerbated susceptibility to a lethal high- or low-dose infection and harbored higher bacterial numbers than did wild-type (WT) mice.
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